The primary hypothesis is that low-dose Lupron at 5-day intervals will stimulate pituitary-gonadal function in men with hypothalamic gonadotropin deficiency. This is an extension of an approved protocol (#6836) from diagnostic use of Lupron involving 5-day spacing of injections to a) evaluation in women up to 3 weeks and b) long-term therapy in hypogonadotropic individuals. The aim dealing with diagnostic use in teenagers is already approved as #6836 and #6585 and the attached budget does not address those already-approved studies.